Controlling means for refrigerating apparatus



May 18, 1937. i J. KIRGAN El AL CONTROLLING MEANS FOR REFRI GERA TINGAPPARATUS Filed Ocil, 24,.1934 2 S hees$heet 1 (Id r are! r mmw Wm. M Kwnmu m ay 1937. J. KIRGAN El AL CONTROLLING MEANS FOR REFRIGERATINGAPPARATUS 2- Sheets-Sheet 2 Filed Oct. 24, 1934 {NVENTORS 0 u z animalG'eo e ,00 g

'Tb'E ATTORNEY.

Patented May 18, 1937 UNITED STATES CONTROLLING MEANS FOR REFRIGERAT-ING APPARATUS John Kirgan, Easton, Pa., and George H. Woodard,Phillipsburg, N. J., assignors to Ingersoll- Rand Company, Jersey City,N. J., a corporation of New Jersey Application October 24, 1934, SerialNo. 749,704 12 Claims. ((162-152) This invention relates torefrigerating apparatus, and particularly to controlling means for arefrigerating system in which the necessary effect is obtained bycooling and circulating a suitable refrigerating medium.

The invention is particularly designed for use in connection with arefrigerating system comprising a vessel in which a liquid refrigerant,such as water, is chilled, and from which it is conducted to the placewhere the refrigerating effect is to be produced. In installations ofthis kind, the refrigerant is oftentransmitted to a considerably higherlevel than the vessel or evaporator in which the temperature of therefrigerant is diminished, so'that the water or other liquidrefrigerant, as it flows back to the evaporator to be again chilled,travels from a higher point to a lower one. Proper control of thereturning water to enable the output to be reduced as working conditionsrequire, or to prevent flooding of the evaporator, when the operation ofsuch a system is stopped or in the event of a mishap, or for otherpurposes, is therefore desirable.

The principal object of this invention is to provide a simple andemcient controlling arrangement for refrigerating apparatus of thiskind.

A) further object of the invention is to provide refrigeratingapparatus, having means in the form of one or more valves, disposed tobe actuated and released through the instrumentality of the refrigerantitself, to facilitate controlling the system in the manner above stated.

Other objects and the nature and advantages of theinvention are fullydescribed hereinafter, and several constructions in which the inventionis embodied are illustrated in the accompanying drawings. Thedisclosure, however, is by way of explanation only, and we may makechanges in the shape, size and arrangement of the various parts withoutgoing beyond the principle of the invention or exceeding the spirit andscope of the claims appended hereto.

On the drawings, Figure 1 shows one embodiment of the invention, and

Figure 2 shows a modification. With reference to Figure 1, in which someof the parts appear in vertical section, the numeral l indicates avessel called an evaporator to which water is supplied by a pipe 2. Thispipe has inlet branches 3 and 4 entering chambers 5 and 6 respectivelyin the evaporator I. In each of these chambers the water is dischargedthrough an inlet header 1 having a number of openings to enable thewater to issue in the form of a spray.

By suitable evacuator devices (not shown) the, pressure in theevaporatorchambers 5 and 6 is greatly reduced, so that the water, whichenters at a given temperature, is partly vaporized. The

, vapor thus formed is removed from the evapo- 5 rator by the said.evacuators' and carried into a condenser (not shown) to be liquefied.The process of vaporization extracts some of the heat from-the remainingwater and thus the temperature of the main body ofthe water isdecreased. 10 The chilled water at the bottom of the chambers 5 and 6 isdelivered to a. pipe 8 connected to the chambers 5 and 6 throughbranches 9, and through the pipe 8 the chilled water flows to the placewhere refrigeration is to be accomplished. 15 I In 'each of the branchpipes 3 and 4 is a valve 10 in a casing II, the casings havingextensions l2 containing dlaphragms l3 over the ends, and to these endsare attached caps l4 which secure I the diaphragms in place. The stemsof the valves project into the extensions i2 and have heads l5 which arepressed against the diaphragms by spring elements It, encircling thevalve stems and engaging the heads 15 at one end and the inside of theextensions I 2 with the other. The 25 springs l6 tend to close thevalves, but when sufiicient pressure acts on the diaphragms l3 thevalves will open, and then water is admitted to both of the chambers 5and 6. a

At i1 is indicated a branch pipe which leads 30 from the deliveryconduit 8 to the valve casings II and is connected to the caps i4 sothat pressure can be exerted on the diaphragms I3. This pipe I! containsa valve element l8 between the two valve casings H, said valve beingshown as 5 a poppet valve although any suitable .type may be used. Thisvalve is normally closed by theweight of the magnetic plunger 20 of thesolenoid 2i, its stem l9 protruding from the pipe I! and being aflixedto said plunger. This solenoid is40 united by conductors 22 to theelectrical power circuit 23 which may furnish current'to other parts ofthe apparatus, such as the motor for the pump 42 in the line of theconduit 8. In.the line of one of the conductors 22 is a fixed con- 45tact 24 and a movable contact 25. The latter is connected by a link 26to the movable end of an expansible casing 21. The opposite end of thiscasing is fixed and is connected bya piece of tubing 28 to a bulb 29which is mounted in the 50 conduit 8 .and is subject to the temperatureof the chilled watertherein. The tube 28 and bulb 29 together with thecasing 21 are filled with an expansible fluid, and when this fluidcontracts, due to the chilled water falling to a certain tem- 55 2a,oso,soa

perature, the contacts 24 and 25 will be separated. At full load whenthe temperature of the chilled water is not so low as at part load, andwhen the apparatus is not operating, these contacts engage 5 each other,because the circuit to the solenoid 2| is then closed and the latter isenergized.

The contents of the conduit 8 we impelled by the pump 42 to' a coolingcoil 43 in which the chilled water absorbs heat, and which is con- 10nected to the return pine 2. The conduit 8 may contain therein at any"suitable point, a check valve 44, this check valve being preferablylocated between the pipe I! and coil 43. In the end of the pipe I1,beyond the two valves i0, is a hand operated valve 30 which may bepermanently open slightly to'give a constant leakoif, and through whichthe contents of this pipe may be discharged. The pipe 2 may also containa hand control valve 45'.

In operation, with' the valve 45 open, the chilled water withdrawn fromthe chambers 5 and 6 through the conduit 8 and impelled to the coolingcoil 43 by the pump 42 will be under some pressure. This pressure willbe transmitted to the pipe l1, and the water therein will act upon thediaphragms of the controlling valve means l0 and force these valves toopen position to admit fluid to both the chambers 5 and 5. Both of thevalves to will remain open so long as the valve I8 is open. But if thisvalve I3 is closed, the adjacent valve Ill for the chamber 5 will beforced to close, leaving the other valve open and the chamber 6 alone inoperation. Therefore, so long as the system operates at full capacity,water will be chilled in both compartments 5 and 6; but in the eventthat the pump 42 is shut down to stop the system, or if this pump failsso that no more chilled water is im-' pelled through the conduit 8, thenecessary pres- 40 sure will no longer be exerted on the diaphragms l3.Both the valves III will therefore close and the water from the coil 43will not drain back into the evaporator and flood it.

Likewise when the load drops, and the water does not absorb so much heatin the coils 43, but comes back cooler to the evaporator I, thetemperature of the water in the pipe 8 falls and causes a contraction ofthe fluid in the casing 21, tube 28 and bulb 29.' Then the circuit willbe open to the solenoid 2|. The plunger 20 now can drop and the plunger20 can move the valve '8 to closed position. The branch 3 will then beclosed, but the branch 4 will remain open and the chamber 5 willcontinue to work.

Hence, the system'is protected against flooding of the evaporator incase the chilled water Dump fails, and the system is automaticallyregulated for part-load conditions by cutting out the chamber 5. Thisalso tends to prevent freezing 0 of theevaporator by cutting out onechamber when the chilled water gets too .cold. The cost of the system islow and the friction of the water in the pipes 3 and 4 is balanced bythe use of similar branch pipes, similar valves and similar headers I.

The construction shown in Figure 2 operates in the same manner, exceptthat the branch inlet member, 3 alone has a diaphragm-actuated valve Ill. Figure 2 is a top plan view partly in section. In the branch inletmember 4 there is a disc 3| having a pressure-reducing openingorthrottling orifice 32, this disc being held in place by flangedcoupling members 33 on the adjacent ends of the pipe sections making upthe branch 4, The opening a: is so designed that and enables the valveill in the branch 3 to close, 5 I

so as to prevent any more water from entering the chamber 5. Thischamber is thus cut out at part load inthe same way as described inregard to Figure 1.

To prevent draining into the evaporator and 10 flooding the latter whenthe pump 42 is stopped or fails, a second valve Illa is placed in theline of the inlet member or main supply pipe 2 in advance of thebranches 3 and 4. This valve is in all respects like the valve III inthe branch 3 and 15 is opened by pressure on the diaphragm l3. The capl4a over the diaphragm l3 of the valve Ila in the inlet member or pipe 2is also joined by way of a pipe 38 to the pipe l1.

Therefore, when the system is shut down, or if 2 an accident happens tothe pump 42, the valve means Ilia in the pipe 2 closes and returningwater is cut off entirely from the branches 3 and 4. The closing ofvalve Ila takes place because there will be no more pressure in the pipeI! 25 when the pump 42 stops. With valve l3 as shown in Figure 2, thevalve ill will then.also close; but if the system is already operatingat part load,

and the valve H! has cut off the valve III, the

valve Illa alone closes, cap I4 of valve l3 drain- 30 ng by way of valve30.

To supply water to the pipe 2 to make up for loss, and thus replenishthe system, a pipe 43 is connected to the evaporator, communicatingtherewith, for example, through the bottom of 35 the chamber 5. The pipe40 contains a rotary valve 35 with an outside arm connected by a link36, slidably mounted in the wall of the evaporator, to a float-bearinglever 3! in the chamber 6. This lever is a bell crank mounted to move up40 and down in this chamber.

As long as the return water is plentiful the valve in the pipe 40 willbe shut or nearly so, but if the system begins to run short of water thelevel of the liquid in the chambers 5 and 5 on the bottom will fall, sothat the float lever 31. sinks and opens the valve 35 to a greaterextent, and admits more make-up water into the chamber 6. On the otherhand, a high level of water a in the evaporator will keep the valve 35closed. 50 The amount of the make-up water is therefore determinedautomatically and is admitted in greater or less degree as conditionsdemand. The vapor liquefied in the condenseris returned to theevaporator in the usual manner, but the pipe 55 40 is needed in practiceto make up any other losses that may occur.

The system in Figure 2 thus answers all the purposes of the system shownin Figure 1, besides automatically governing the admission of make- 60up water. The action of the valves is smooth and continuous, and theadmission of make-up water is very uniform and regular.

The evacuating devices mentioned above for removing vapor from thechambers 5 and 3 will 65 preferably have the form of centrifugalcompressors, which have lately proved very successful for this purpose,and wheirthe chamber 5 is cut out by the valve It, the evacuating meansfor that chamber is rendered ineffective in any 7 feasible manner. whenthe entire apparatus is stopped, the evacuating means for the remainingchamber or chambers is likewise put out of action. flSteam jetevacuators may also be employed.

evaporator having chambers, a refrigerant inlet member for each chamber,a discharge conduit connected to said chambers, valves in each inletmember, means dependent upon the refrigerant in the discharge conduit tocontrol said valves. and additional means for separately controlling oneof said valves.

3. Refrigerating apparatus comprising an evaporator having chambers,inlet members to admit refrigerant to the chambers, a discharge conduitconnected to said chambers, a valve in one of said inlet members, avalve for all said inlet members, means dependent upon the re frigerantin the discharge conduit to actuate said valves, and additional meansfor separately controlling one of said valves.

4. Refrigerating apparatus comprising an evaporator to receive and coola refrigerant and then discharge same, inlet members to admitrefrigerant to the evaporator, means dependent upon the pressure of thedischarged refrigerant for separately determining the rate of flow ofrefrigerant through each of said members, and additional meansinfluenced by the discharged refrigerant for separately controlling oneof said members.

5. Refrigerating apparatus comprising an evaporator for a refrigerantwith chambers each having an inlet member for the refrigerant, adischarge conduit connected to the chambers, a valve ineach of saidmembers, means dependent upon the pressure of the discharged refrigerantto actuate said valves, and additional means controlled by thetemperature of the discharged refrigerant for independently controllingone of said valves.

6. Refrigerating apparatus comprising an evaporator having chambers,inlet members to admit refrigerant to the chambers, a valve for one ofsaid inlet members, a valve for all of said members, a discharge conduitconnected to said chambers, means dependent upon the pressure of thedischarged refrigerant to actuate said valves, and additional means forseparately controlling one of said valves.

'l. Refrigerating apparatus comprising an evaporator having chambers toreceive a refrigw erant, inlet members to admit refrigerant to thechambers, a discharge conduit connected to the chambers, means dependentupon the discharged refrigerant to control said inlet members, andadditional- .means dependent upon the temperature of the dischargedrefrigerant for separately controlling .one of said members. 7

8. Refrigerating apparatus comprising an evaporator having chambers,inlet members to admit refrigerant to the chambers, a discharge conduitfor the chambers, a valve for theinlet member of one of said chambers, asecond valve common to all saidmembers, means dependent upon thedischarged refrigerant to control all said valves, and means dependentupon the temperature of the discharged refrigerant to control separatelythe first of said valves.

9. Refrigerating apparatus comprising an evaporator having chambers toreceive a refrigerant, inlet members to admit refrigerant to thechambers, refrigerant discharge means in-- cluding, a conduit connectedto the chambers, means dependent upon the pressure of the dischargedrefrigerant to control said inlet members, and means dependent upon thetemperature of the discharged refrigerant to separately control one ofsaid members.

10. Refrigerating apparatus comprising an evaporator having chambers,inlet members to admit refrigerant to the chambers, a discharge conduitconnected to the chambers, a valve for one of said inlet members, avalve common to all of said inlet members, means dependent uponthepressure of the discharged. refrigerant to control said common valve,and additional means dependent upon the temperature of the dischargedrefrigerant to control separately the first of said valves.

'11. The combination with an evaporator having inlet and outlet membersfor refrigerant, of means for controlling the inlet members comprisingpressure-actuated valves therein, means for supplying pressure medium toactuate the valves, control means in the supply means arranged toisolate some of said valves from the pressure medium withoutinterrupting actuation of the remaining valves, andelectrically.controlled means for actuating said control means and foreffecting said isolation in accordance with the temperature of therefrigerant leaving said evaporator.

12. Refrigerating apparatus comprising an J0me mom. oaoma H. WOODARD.

